Session: 04-28 Emissions Hydrogen/Ammonia I

Paper Number: 153221

Measurements of CO and NOx Emissions From Premixed Turbulent Methane/Hydrogen Flames 

The growing interest in utilization of hydrogen-blended fuels for energy production in gas turbines is driven by the need to meet stringent emissions regulations. Hydrogen, at the same equivalence ratio, burns at a higher flame temperature and exhibits nearly four times the unstretched laminar flame speed compared to methane. This poses challenges for flame stability in premixed low NOx combustors. In addition to the higher diffusivity of hydrogen, the highly turbulent environment in which these combustors operate creates local hotspots with compositions that differ from the average reactant mixture. These hotspots can reach temperatures much higher than the average flame temperature expected based on the mixture- averaged equivalence ratio. As a result, this can lead to increased levels of thermal NOx from lean, high hydrogen flames as compared to what would otherwise be expected from these mixtures. Therefore, it is vital to understand the impact of flow turbulence on emissions from high hydrogen blended flames. In this study, single-point emissions measurements were conducted on turbulent premixed hydrogen-enriched methane flames from a contoured nozzle Bunsen burner with variable turbulence. The influence of turbulence on NOx and CO emissions was investigated under two key conditions: (a) constant flame temperature and (b) constant unstretched laminar flame speed. Emissions were measured at varying residence times and incoming flow turbulence intensities. To gain insights into the role of turbulence and flame strain on emissions, experimental results were compared with 1D laminar flame simulations.  

Presenting Author: Haripriya Rajagopalan Georgia Institute of Technology

Presenting Author Biography: Hari Priya is a 5th year PhD candidate in the aerospace engineering department at Georgia Tech

Authors:

Haripriya Rajagopalan Georgia Institute of Technology
Ben Emerson Georgia Institute of Technology
Vishal Acharya Georgia Institute of Technology
David Noble EPRI
Tim Lieuwen Georgia Institute of Technology